Methods for Heart Rate Variability Biofeedback (HRVB): A Systematic Review and Guidelines.
Level 1 - systematic review of randomized trials
Systematic review of 143 studies
PubMed 36917418 · doi:10.1007/s10484-023-09582-6
What was done
Authors systematically reviewed HRVB protocols across PsycINFO, CINAHL, Medline, and Web of Science from 2000 through April 2021 following PRISMA guidelines. The review evaluated studies from any field or population to describe protocol variants and assess reporting quality.
What was found
Across 143 included studies, three distinct HRVB protocols were identified: Optimal resonance frequency (RF) (n = 37, breathing at previously detected individual RF), Individual RF (n = 48, breathing guided in real time by biofeedback device data), and Preset-pace RF (n = 51, fixed breathing rate, usually 6 breaths/minute). Marked variation existed in total weeks, breathing duration, and laboratory versus home session combinations. Almost two-thirds of studies failed to provide sufficient detail to replicate protocols regarding breathing duration, inhalation/exhalation ratio, breathing control, or body position.
Why it matters
Substantial methodological heterogeneity and widespread under-reporting hinder reproducibility and cross-study comparisons in heart rate variability biofeedback research.
Limits
The review evaluates protocol methodology and reporting completeness rather than quantifying clinical or physiological effect sizes. Specific risk-of-bias metrics and outcome data across individual trials are not reported in the abstract.
Cited by
- supports Slow breathing at six breaths per minute superimposes high-frequency respiratory sinus arrhythmia onto low-frequency Mayer wave oscillations, markedly increasing measured heart rate variability.